Double-acting solenoid pump



1966 W. v. BLACKWELL ET AL 3,

DOUBLE-ACTI NG SOLENOID PUMP Filed Dec. 28. 1964 s m ,TK R mm m5 2ATTORNEY United States Patent 3,282,219 DOUBLE-ACTING SOLENOID PUMPWayne V. Blackwell, 3721 Cardinal Ave., and Lee R. Stark, 2819 NilesSt., both of Bakersfield, Calif. Filed Dec. 28, 1964, Ser. No. 421,581 7Claims. (Cl. 103-53) This invention pertains to a double-acting solenoidpump and, more particularly, to a pump of the type intended to besubmerged in a fluid to be pumped thereby into a pipe or similarconduit. A pump of this type is especially adapted for use within a wellcasing and particularly a casing of substantial depth not very welladapted to the use of well rods to operate bottom valves and the like.

Various types of solenoid-actuated pumps have been devised heretoforebut most of these have been of the type effecting the pumping operationwhen the solenoid is operating only in a single direction. Pumps of thistype have been employed for example, as fuel pumps for motor vehiclesand the like.

In contrast to such aforementioned solenoid pumps which effect pumpingwhen operating in only one direction, it is the principal object of thepresent invention to provide a very compact, eflicient, and economicallyoperable pump employing a reciprocable armature preferably operatedwithin a pair of longitudinally aligned solenoid coils mounted influid-tight manner within a pump housing or casing adapted to besubmerged within liquid fluids to be pumped thereby, and particularlyfluids in relatively deep wells such as oil wells or the like, thearmature within the solenoid serving as a piston within a pump cylinderand pumping being effected by the opposite ends of said piston-armatureduring both directions of reciprocable movement thereof within the pumpcylinder.

Another object of the invention is to provide a relatively simple,preferably cylindrical outer housing having heads in opposite endsthereof, said heads each being provided with both inlet and dischargevalves which are cooperable to effect unidirectional flow of fluid froma single discharge port in said pump housing.

A further object of the invention is to provide such pump housing withfluid inlet ports respectively adjacent the opposite ends thereof toimplement the intake of fluid by said pump and said aforementioned valvestruc tures are such as to accommodate the inlet of fluid to the pumphousing at said opposite ends thereof while providing for only a singledischarge port from said pump housing.

Still another object of the invention is to provide relatively simpletypes of check-type valves in the opposite end portions of the pumphousing, said valves preferably being arranged so that the movablemembers of each may be actuated by gravity to move to the valve seats ofeach valve and thereby close the same.

A still further object of the invention is to provide, in the preferredconstruction of the double-acting solenoid pump comprising the same, adesign which permits formation of a number of the essential housingmembers and pump cylinder from standard types of tubing or pipe stock,only simple threading operations being required to permit assembly ofsaid members with housings and the like otherwise included in the pumpconstruction.

Details of the foregoing objects and of the invention, as well as otherobjects thereof, are set forth in the following specification andillustration in the accompanying drawing comprising a part thereof.

3,282,219 Patented Nov. 1, 1966 In the drawing:

FIG. 1 is a vertical sectional view of a pump embodying the principlesof the present invention and connected to a fragmentarily illustratedlower end portion of a well tube or pipe, the pump being shown as beingdisposed within a fragmentarily illustrated portion of a well casing orbore hole.

FIG. 2 is a transverse sectional view of the pump taken on the line 2-2of FIG. 1.

FIG. 3 is a transverse sectional view taken on the line 33 of FIG. 1.

FIG. 4 is a transverse sectional view taken on the line 44 of FIG. 1.

Referring particularly to FIG. 1, it will be seen that the pump 10,which embodies the preferred constructions and details of the presentinvention, is illustrated as being connected to the lower end of afragmentarily illustrated well tube or pipe 12 so as to depend therefromand receive fluid discharged from said pump at the upper end thereofinto said well tube 12. FIG. 1 also illustrates the pump 10 beingdisposed substantially longitudinally within a well casing or bore hole14 which is only fragmentarily illustrated. It is to be understoodhowever that, although the construction and proportions of the designare well adapted to the pump being accommodated within a well casing orbore hole, the pump may be employed in any other volumes of fluids whichare to be pumped such as those contained in tanks, natural formations orthe like. Also, while the design of the pump readily lends itself topumping petroleum and similar products from wells of substantial depth,the structure of the pump is actually such as to adapt it to pump fluidsof various other types but preferably those which are liquid.

The pump 10 comprises a preferably cylindrical outer housing 16 whichmay be formed from conventional pipe or tube stock, the opposite ends ofwhich are preferably internally threaded respectively to receivecomplementarily threaded portions of upper head 18 and lower head 20 ofthe pump to connect the same detachably to said outer housing. Extendingcoaxially within the outer housing 16 is an inner housing 22 which alsomay be formed from conventional tube or pipe stock and is externallythreaded, for example, at the upper end thereof, to be received withinand connected to the inner cavity 24 within upper housing 18, while thelower end of the inner housing 22 preferably is internally threaded toreceive an annular locking collar 26 which also is internally threadedfor purposes to be described. The inner housing 22, while concentricwith outer housing 16, is of smaller outer diameter than the innerdiameter of outer housing 16, thereby providing an annularfluidconducting space 28 between the two housings.

A pump cylinder 30 is concentrically mounted within the inner housing 22so as preferably to be exactly coaxial therewith and thereby provide alongitudinal-1y extending annular space there-between to accommodatepreferably a pair of solenoid coils 32 and 34 which, if desired, mayhave an annular insulating member 36 mounted therebetween and alsosurrounding the pump cylinder 30. The solenoid coils 32 and 34preferably closely surround the pump cylinder 30 and otherwise arecompactly disposed within inner housing 22 to render thbe1 entireconstruction of the pump as compact as poss1 e.

So as to contain the solenoid coils 32 and 34 in fluidtight conditionwithin the interior of the pump 10, annular sealing members 33 and 40,which preferably are formed from insulating material, are mounted intight engagement respectively with the inner housing 22 adjacentopposite ends thereof, and the opposite ends of the pump cylinder 30.Any desired type of connection between the sealing members and such pumpcylinder and inner housing may be used which will be disposed adjacentthe opposite ends of the assembled pair of solenoid coils 32 and 34 andmaintain the same in fluid-tight condition. Expansible-type packingmaterial is suitable for this purpose and may be maintained againstmovement with respect to pump cylinder 30 by means of diametricallyextending cross-pins 42 and 44 which also are projected across theinterior of pump cylinder 30 for the additional purposes of serving asupper and lower stops to limit the reciprocable movement of thecombination armature and pump piston 46 within the pump cylinder 30. Theouter perimeter of the sealing members 38 and 40 preferably are tightlydisposed within seats 48 and 50 extending inward from opposite ends ofthe inner housing 22.

The combination armature and pump piston 46 preferably freelyreciprocates within the pump cylinder 30, in opposite axial directions,when the solenoid coils 32 and 34 are energized successively by means tobe described. The opposite ends of the armature-piston 46 preferably areimperforate and, in the most desired design of the pump, thearmature-piston is of a solid, ferrous construction. However, annularpacking ends 50 of suitable, conventional type are provided around thesame adjacent opposite ends thereof for slidable engagement with theinner walls of the pump cylinder 30 and thereby provide efficientpumping of fluids in opposite ends of the pump cylinder 30 without undueleakage past the ends of the armature-piston 46.

The lower head 20 has a preferably central inlet opening 52 thereinwhich is concentric with a valve seat 54 which accommodates a movablevalve ball 56 to comprise a check valve. A short, externally threadedsleeve 58 is threaded into locking collar 26 for support thereby and theinterior of said sleeve comprises a passageway 60 between the interiorof pump cylinder 30 and inlet opening 52, all of the same being coaxial.The sleeve 58 also provides a space compactly accommodating valve ball56 when the lower central valve comprising said ball and valve seat 54is open for the inlet of fluid to the lower end of the pump 10. However,upward movement of the valve ball 56 is limited by cross-pin 44 and, dueto the size and weight of valve ball 56, it will quickly move, bygravity, as well as fluid pressure, against valve seat 54 when closingof the valve is to occur.

The lower head 20 also is provided with discharge valve means comprisingan inner circular cavity 62 which is directly above and communicateswith the valve seat 54 and extends upward to an upper valve seat 64. Aseat ring 66 also may be threaded upon the lower end of the short sleeve58 and thereby comprise a composite upper valve seat 64 against which amovable discharge valve member 68, comprising a flat, annular ring ofsuitable material, may abut when the valve is to be closed. Tofacilitate such closing, light spring means 70 may be employed betweenthe valve member 68 and the lower surface of locking collar 26, forexample, to insure that valve member 68 will be at least lightly biasedtoward closing position under operating conditions to be described.Discharge passage means 72 communicate with the valve seat 64 to permitthe flow of fluid from inlet opening 52, past the valve seats 54 and 64,and into the annular longitudinally extending space 28 within the outerhousing 16.

The upper head 18, for convenience of construction and assembly,actually comprises an upper collar 74 which is threadably connected intothe upper end of a head body 76. The upper end of the collar 74 isinternally threaded to be connected detachably to the threaded lower endof well tube 12. The head body 76 has a preferably central opening 78which is coaxial with the pump cylinder 30 and armature-piston 46 so asto communicate directly therewith. The opening 78 extends into a shallowcircular seat 80 comprising part of inlet valve means which also includea plurality of valve inlet passages 82 which extend radially inward fromthe exterior of the pump and terminate in upwardly extending dischargeends which intersect the valve seat 80 against which the annular, flatmovable valve member 84 abuts when the valve is in closed condition. Thecentral opening 86 of said inlet valve member preferably is coaxial withopening 78.

The head body 76 also is provided with another circular, shallow seat 88which receives a flat, circular valve seat member 90 comprising part ofthe discharge valve of upper head 18, the movable valve member of whichcomprises a ball 92 which coacts with the valve seat 90 to comprise acheck valve.

The fluid discharge passages 94 are formed within the upper head 18 atcircumferentally spaced locations. As best shown in FIG. 1 andespecially in FIG. 2, these passages extend in an axial directionupwardly from the lower ends of the head 20 and then extend inwardlytoward the central discharge opening 96 of the upper head 18.

Any suitable, relatively simple electric circuit may be employed tooperate the solenoids 32 and 34 in sequence or as to energize them anddeenergize them in succession at a rate selective in accordance with thepower requirements of the pump which, in turn, is designed to eflect aunidirectional flow of fluid through the well tube 12 in accordance withthe depth of the well, for example, the viscosity of the fluid, thefrictional characteristics of the pump elements and various otherfactors commonly found in pump operations. To accomplish thereciprocation of the combination armature-piston 46 at any such designedand selected cycle or rate of operation, relatively simple control meansmay be employed such as a preferably quick-acting single-pole,double-throw switch 98, the poles of which respectively are connected tothe upper end, for example, of solenoid coil 32 by means of conduit 100,while the lower end of solenoid 34, for example, is connected to theopposite pole of the switch 98 by means of conduit 102. The lower end ofthe upper solenoid coil 32 and the upper end of lower solenoid coil 34may be grounded commonly by conduit 104. Direct current preferably isemployed to energize the solenoid coils 32 and 34. The preferably quickshifting of the movable member of switch 98 between the poles thereof,at a desired cycling rate, can be performed by any suitable mechanismsuch as a continuously driven, variable speed electric motor ofrelatively low power rating, or the like.

Operation of the pump Following the submersion of the pump 10 into abody of fluid, preferably liquid, such as might be contained in a wellcasing, bore hole 14 or the like, the cycling operation of the switch 98is instituted. Upon energizing the upper solenoid coil 32 for example,the armature-piston 46 quickly moves upwardly. The suction created bythe lower end of said armature-piston causes inlet valve ball 56 to openrelative to inlet opening 52 to permit fluid to be drawn therethroughinto the cavity 62 and interior of pump cylinder 30. Immediately uponthe generation of such suction by the armature-piston 46, dischargevalve 68 of the lower head 20 is closed against seat 64, therebypreventing any fluid within space 28 from escaping from the lower endthereof. Upward movement of the armature-piston 46 is terminated whenthe upper end of the same engages the stop pin 42. Such upward movementof the armature-piston moves before it fluid which has been drawn intothe upper end of the pump cylinder 30 through the inlet passages 82 ofupper head 18 by means to be described. Such upward movement of thefluid in the upper end of pump cylinder 30 immediately forces dischargevalve member 92 from the seat 90 and the pressure of such fluid operatesagainst the upper surface of inlet valve member 84 to prevent escape offluid through the inlet passages 82.

Immediately upon the armature-piston 46 reaching its upward limit ofmovement, the switch member 98 again moves quickly in cycling manner tode-energize the upper solenoid coil 32 and quickly energize the lowersolenoid coil 34 to effect downward movement of armature-piston 46 Suchdownward movement causes suction at the up per end of thearmature-piston which immediately causes closing of the discharge valveball 92 against its seat 90 and said suction also immediately draws influid through the inlet passages 82 past the inlet valve 84 which alsois opened by such suction, whereby a charge of fluid is drawnimmediately into the upper end of pump cylinder.

Such downward movement of the armature-piston 46, at the lower endthereof, directs fluid pressure immediately against the inlet valve ball56 which forces it against its seat 54 and the fluid previously drawninto the lower end of the pump cylinder 30 during the upward movement ofarmature-piston 46 now is forced through the passageway 60 and throughthe discharge valve 64, 66 into the annular longitudinally extendingspace 28 between the inner and outer housings for discharge at the upperend thereof into the circumferentially space-d fluid discharge passages94 for delivery to the lower end of well tube 12. Such movement of fluidcontinues until the lower end of the armature-piston 46 reaches the fullextent of its downward movement by engagement with stop pin 44,whereupon the switch 98 once more quickly shifts in cycling manner todeenergize the lower solenoid coil 34 and energize the upper solenoidcoil 32, whereupon the above-described cycle repeats itself and so oncontinuously as long as pumping is to be accomplished.

From the foregoing, it will be seen that the pump comprising the presentinvention constitutes a very compact, eflicient, and effective as wellas powerful type of double acting pump, the piston of which is operatedby a pair of suitable solenoid coils which are maintained in fluid-tightcondition, whereby the pump may be operated by immersion thereofdirectly in the fluid to be pumped, such as in a well casing. Inparticular, it will be seen that through the use of fluid-proof typeelectrical conduits, pumps of the type described above and hereinafterclaimed may be employed in wells of substantial depths and operatedeffectively and efliciently with minimum consumption of power andwithout requiring foot valves in the well tube or pipe unless desired.Such pump arrangement and operation also eliminates any need for wellrods to operate pump pistons and the like and, even more particularly,the employment of the particular type of solenoid-operated pumpprecludes the need for expensive types of conventional electric motorssometimes employed in submerge-d pumps but in connection with whichunusual and expensive precautions must be taken to maintain said pumpsout of contact with any fluid.

While the invention has been described and illustrated in its severalpreferred embodiments, it should be understood that the invention is notto be limited to the precise details herein illustrated and describedsince the same may be carried out in other ways falling within the scopeof the invention as claimed.

We claim:

1. A double-acting solenoid pump for immersion in fluid to be pumped andcomprising an imperforate uninterrupted cylinder, a solid cylindricalferrous double-acting piston having imperforate opposed end faces andreciprocable freely Within said cylinder, said piston comprising asolenoid armature, a pair of solenoid coils surrounding the exteriorsurface of at least the opposite ends of said cylinder for supportthereby and separated from each other by insulating means surroundingthe intermediate portion of said cylinder, an imperforate innercylindrical housing extending between and enclosing said coils, saidhousing being coaxial with said cylinder, and the opposite endsextending beyond the ends of said cylinder a limited distance, an outercylindrical housing surrounding said inner housing in radially spacedrelationship and coaxial therewith, upper and lower heads threadablyconnected to the respective upper and lower ends of said inner and outerhousings to connect the same in assembled operative position, said headsbeing no greater in diameter than said outer housing, discharge portmeans in said upper head connectable to a fluid line arranged to receivefluid therefrom for unidirectional flow, inlet ports in both of saidheads communicating with the exterior of said pump, valve means andpassageways in said heads operable sequentially to control and directthe flow of fluid successively inwardly from the inlet ports in saidheads for sequential flow into the opposite ends of said chamber byreciprocation of said piston therein and said check valves functioningat the completion of reciprocation of said piston in one direction toclose and discontinue flow sequentially through said inlet ports andpermit discharge of fluid from said discharge port in said upper head,an electric circuit connected to said solenoid coils and connectable toa source of current, and switch means in said circuit operable at apredetermined rate sequentially to energize and deenergize said coils toeffect free reciprocation of said piston-armature in opposite directionswithin said cylinder to effect substantially constant delivery of fluidthrough said discharge means in said upper head.

2. The pump according to claim 1 in which said lower head has outletmeans communicating with the lower end of the space between said outerand inner housings and said outlet means are operable upon movement ofsaid piston toward said lower head to pass fluid into said space fortransmission to said upper head and through said discharge port therein.

3. The pump according to claim 1 in which said check valves in saidupper and lower heads compnise a balltype and a ring-type in each headand coaxially mounted with respect to eath other, one of said checkvalves in each head normally closing the inlet means therein while theother valve is open relative to the outlet means and vice versarespectively upon reversal of the movement of the piston in the pumpcylinder.

4. The pump according to claim l in which both heads have substantiallycentral bores having ball seats and receiving movable balls comprisingone of said check valves in each head, and ports radially displaced fromthe central axis of each head terminating in valve openings and movablyengageable by circular valve members freely movable toward and from thesame to comprise a second check valve in each head, said check valvesbeing arranged to open and close oppositely to each other in each head.

5. The pump according to claim 1 in which said lower head has an inletport substantially centrally of the lower end thereof communicating withthe exterior of said pump, a ball check valve operable relative to theupper end thereof, radially directed outlet port means in the upperportion of said lower head communicating with said space between saidinner and outer housings, a circular check valve operable relative tosaid outlet port means; and said upper head having an inlet portextending upwardly substantially centrally from the lower end thereof toreceive fluid from the upper end of said pump cylinder, radiallydirected inlet ports extending inwardly from the periphery of said upperhead to receive fluid from the exterior of said pump but terminating inspaced relation to said central inlet port, circular check valve meansmovable relative to the inner ends of said radial inlet ports, a ballseat above said circular check valve and aligned with said central inlet:port, and a ball check valve movable relative to said ball seat andarranged to be moved from closed position upon said ball seat when saidcircular valve is closed to permit the flow of fluid from the upper endof said pump cylinder through the center of said circular valve when thelatter is in said closed position.

6. The pump according to claim 5 in which said radially directed outletports in said lower head communicate with the lower end of said pumpcylinder and said circular check valve is movable to close said portswhen said piston is ascending and said ball check valve in said lowerhead is opened by the suction produced by such movement of said piston.

7. The pump according to claim 5 in which said upper head has passagesextending upwardly therethrough in circumferentially spaced locationsadjacent the outer surface thereof and communicating at the lower endsthereof with the upper end of said space between said inner and outerhousings for transmission of fiuid pumped by the lower end of saidpiston, said passages being spaced between said radially directed inletports in said upper head and being open at all times for suchtransmission of fluid from said space between said housings to saiddischarge port means in said upper head.

References Cited by the Examiner UNITED STATES PATENTS 1,655,825 1/1928Schmidt l0353 2,473,726 6/1949 Payne 10353 X 2,833,220 5/1958 Robinsonet al 103-53 References Cited by the Applicant UNITED STATES PATENTSROBERT M. WALKER, Primary Examiner.

1. A DOUBLE-ACTING SOLENOID PUMP FOR IMMERSION IN FLUID TO BE PUMPED ANDCOMPRISING AN IMPERFORATE UNINTERRUPTED CYLINDER, A SOLID CYLINDRICALFERROUS DOUBLE-ACTING PISTON HAVING IMPERFORATE OPPOSED END FACES ANDRECIPROCABLE FREELY WITHIN SAID CYLINDER, SAID PISTON COMPRISING ASOLENOID ARMATURE, A PAIR OF SOLENOID COILS SURROUNDING THE EXTERIORSURFACE OF AT LEAST THE OPPOSITE ENDS OF SAID CYLINDER FOR SUPPORTTHEREBY AND SEPARATED FROM EACH OTHER BY INSULATING MEANS SURROUNDINGTHE INTERMEDIATE PORTION OF SAID CYLINDER, AN IMPERFORATE INNERCYLINDRICAL HOUSING EXTENDING BETWEEN AND ENCLOSING SAID COILS, SAIDHOUSING BEING COAXIAL WITH SAID CYLINDER, AND THE OPPOSITE ENDSEXTENDING BEYOND THE ENDS OF SAID CYLINDER A LIMITED DISTANCE, AN OUTERCYLINDRICAL HOUSING SURROUNDING SAID INNER HOUSING IN RADIALLY SPACEDRELATIONSHIP AND COAXIAL THEREWITH, UPPER AND LOWER HEADS THREADABLYCONNECTED TO THE RESPECTIVE UPPER AND LOWER ENDS OF SAID INNER AND OUTERHOUSINGS TO CONNECT THE SAME IN ASSEMBLED OPERATIVE POSITION, SAID HEADSBEING NO GREATER IN DIAMETER THAN SAID OUTER HOUSING, DISCHARGE PORTMEANS IN SAID UPPER HEAD CONNECTABLE TO A FLUID LINE ARRANGED TO RECEIVEFLUID THEREFROM FOR UNIDIRECTIONAL FLOW, INLET PORTS IN BOTH OF SAIDHEADS COMMUNICATING WITH THE EXTERIOR OF SAID PUMP, VALVE MEANS ANDPASSAGEWAYS IN SAID HEADS OPERABLE SEQUENTIALLY TO CONTROL AND DIRECTTHE FLOW OF FLUID SUCCESSIVELY INWARDLY FROM THE INLET PORTS IN SAIDHEADS FOR SEQUENTIAL FLOW INTO THE OPPOSITE ENDS OF SAID CHAMBER BY